Footwear of known designs and configurations have utilized selectively changeable ornamental features, such as decorative emblems, straps, and the like. By and large, these ornamental features were integrated over existing, functional features in the footwear, usually along the top portion of known footwear embodiments. The advantage of these ornamental features related to the users ability to have single item whose appearance could be reconfigured to reduce the number of different pieces of footwear that person might need. However, the functioning aspects of these shoes was not altered, and a person desiring footwear with greater traction would still need to purchase completely separate shoes.
In response, more functional, interchangeable spikes and/or cleats were designed to be removable from the sole. Here, the user was able to remove or replace these spikes in order to attain better traction with a single shoe. Alternatively, a cavity may be formed across the bottom of the sole, with a replaceable traction plate fitting in the cavity. Examples of such footwear can be found in U.S. Patent Publication 2010/0223809 and U.S. Pat. Nos. 7,520,069 and 5,836,090.
Separately, extraneous devices have been developed to removably fit over existing footwear to improve traction. In effect, these removable devices are not specific to any single piece of existing footwear and, instead, are designed to cooperate with a wide array of shoes, usually by engaging the wearer's foot across both the heel and toe area. Examples of such devices can be found in U.S. Pat. Nos. 8,510,974; 6,154,982; and 5,689,901.
Other designs have attempted to emphasize simplicity and versatility in a sandal-like shoe. U.S. Pat. No. 5,802,738 describes a shoe held together by an upper and engagement mechanism which penetrate through apertures in the sole so as to avoid the need for gluing the sole and the upper. U.S. Pat. No. 7,823,299 discloses footwear that is convertible between a flip-flop and a sandal by repositioning a heel and/or forefoot band between a storage and use-based positioning integrated within the sole.